Linking broadcast television programs to the Internet has been discussed in the prior art. One desired feature is to be able to switch back and forth between a broadcast program and a related Internet site on the World Wide Web. In such manner, normally passive broadcast television becomes an interactive medium.
To access a related Internet site content, the viewer pushes a button on the remote control or clicks a pointing device on an icon on the screen. The user may switch back and forth between Internet content and broadcast content. A typical pointing device for user interface, may consist of either a mouse, track ball, cursor buttons or like type of device. In such manner, the viewer may switch from one Internet site to another during the broadcast program.
Internet content may also be overlaid on broadcast content. World wide web content may be displayed in a window while the broadcast content is still being displayed (picture in picture). Alternately, a transparency such as text may be overlaid on the broadcast television image. In such manner, the viewer simultaneously views broadcast video and interactive Internet content.
Many television programmers (content providers) already have both a video channel and a web site. An application of particular interest to such programmers is to link their video channel and their web site. Linking broadcast video to another medium is sometimes called “simulcasting” after the practice of linking the audio program of a video channel to an FM stereo broadcast.
In some cases, such as a news channel (as for example, Cable News Network), the web site (http://www.cnn.com) represents an alternate form of substantially the same or similar content as contained in the broadcast video channel. In other cases, such as a music or movie channel, the web site represents a supplement to the content of the video channel. The web site may deliver scheduled programming times, additional advertisements, and catalog style ordering of merchandise related to the broadcast video content. Thus, a music channel can sell compact discs of the current music video selection. A shopping channel can provide additional product information relating to the item on sale. In general, a programmer's web site can supplement and expand upon its broadcast video material.
The ability to provide a wealth of product details is of particular interest to advertisers includes providing more detailed information about the product being advertised. An automobile advertisement, for example, may contain an icon representing the automobile manufacturer. Clicking on the auto manufacturer's icon takes the viewer to the web site of the manufacturer, for additional product information.
Although the goal of linking broadcast television and interactive Internet access is known, the implementation of a practical system is a technical challenge. Typically, to link a broadcast television video signal to a specified Internet address, a uniform resource locator (or URL) is formatted onto a tag inserted into the broadcast television signal by the broadcaster (i.e., by the programmer, advertiser or content provider). The inserted tag defines the Web page and identifies the URL where the related Internet information is located. The requirement of a tag in the broadcast television signal, in turn requires that a universal standard as to location and format of the tag be adopted.
Also, other attempts at providing Internet access over MPEG-2 digital TV, involve first decoding the Internet World Wide Web HTML page into a page of video, then encoding page of video into MPEG-2 format, and then broadcasting the MPEG-2 formatted Web pages over the digital TV network. Encoding pages of video into MPEG-2 requires the broadcast source have one or more MPEG-2 encoders. It would be desirable to provide a system that transmits Internet World Wide Web pages without requiring an MPEG encoding process at the broadcast headend.
Decoding HTML pages to video and then into MPEG-2 also means that the MPEG-2 decoder at each viewer location is occupied whenever it is decoding MPEG-2 encoded Web page video. Thus, in the prior art, in order to view both broadcast video and Internet content simultaneously, two MPEG-2 decoders would be required at the viewer location. It would be desirable to provide a system that permits Internet World Wide Web pages and MPEG-2 broadcast video to be displayed without requiring a second MPEG-2 decoder.
Furthermore, Internet connectivity typically requires two way data paths. The return path is used to transmit viewer selections such as mouse clicks and typed commands. At the present time only 15% of the cable television (CATV) systems are capable of two-way transmission over the cable path. The majority of CATV systems remain one way transmission only. Another option for two-way Internet connectivity is to use the public switched telephone network as the return path. However, the use of the public switched network requires a telephone modem and also occupies the household telephone line. It would be desirable to implement interactive Internet access on a one way CATV network without a telephone connection.
Further, there is a latency problem associated with coupling broadcast video content to an Internet site. Selecting an icon before accessing the Internet may mean a long wait, because Internet access and connection must be established, and then the desired HTML page downloaded. That is, first the modem and Internet service provider must establish Internet access (via two way CATV or telephone return), then the connection to the desired web site must be established, and then the HTML page must be downloaded.
Even if the viewer is already connected to the Internet (via two-way CATV or telephone return) when an icon is selected, there may still be an unacceptably long wait for a selected Web page to appear. The waiting time results from establishing a connection through Internet switches from the viewer's home to the remote web site, and then downloading the HTML page. It would be desirable to implement interactive Internet access with a quick response time, not requiring establishment of Internet access, Internet connection and subsequent downloading from the remote web site.
Finally, there is a major traffic problem associated with coupling broadcast video content to a remote Internet web site. If even a small fraction of viewers of a mass-market advertisement clicked on the advertiser's icon, it would result in a deluge of simultaneous telephone connection requests at the advertiser's web site. To accommodate the huge number of requests would require an enormous amount of telephone line capability (and computing power to serve HTML pages) at the remote Internet web site. The resulting number of connection requests would overwhelm most web site traffic models which are designed to support an average number (not a peak number) of connection requests. Yet, coupling broadcast content to Internet content tends to encourage a peak number of simultaneous requests for connection.
It would be desirable to support a mass quantity of simultaneous Internet access requests without requiring an excessive number of simultaneous telephone connections at the remote Internet web site.